﻿CANYON 
  FERRY 
  FOSSIL 
  VERTEBRATES 
  — 
  ^WHITE 
  

  

  413 
  

  

  another 
  species 
  does 
  not 
  seem 
  warranted 
  at 
  this 
  time. 
  The 
  antero- 
  

   conid 
  of 
  Ml 
  is 
  always 
  small 
  but 
  the 
  anterior 
  cingulum 
  is 
  variable 
  

   in 
  extent. 
  In 
  one 
  specimen, 
  both 
  the 
  protoconid 
  and 
  metaconid 
  are 
  

   imited 
  to 
  the 
  anteroconid. 
  This 
  variation 
  occrn^ 
  in 
  all 
  three 
  species 
  

   but 
  is 
  not 
  consistently 
  associated 
  with 
  other 
  characters. 
  The 
  

   mesolophid 
  is 
  variable 
  in 
  extent 
  but 
  is 
  always 
  distinct. 
  On 
  M2 
  the 
  

   lingual 
  portion 
  of 
  the 
  anterior 
  cingulum 
  is 
  variable 
  in 
  extent 
  but 
  is 
  

   always 
  distinct. 
  The 
  posterior 
  arm 
  of 
  the 
  protoconid 
  varies 
  in 
  

   length 
  but 
  never 
  extends 
  to 
  the 
  inner 
  border 
  of 
  the 
  tooth. 
  The 
  

   mesolophid 
  is 
  consistently 
  obsolete 
  or 
  absent. 
  On 
  M3 
  the 
  lingual 
  

   portion 
  of 
  the 
  anterior 
  cingulum 
  may 
  extend 
  nearly 
  to 
  the 
  border 
  of 
  

  

  USNM 
  

   18772 
  

  

  Figure 
  46. 
  — 
  Occlusal 
  view 
  of 
  the 
  type 
  (USNM 
  18772) 
  of 
  Eumys 
  latidens, 
  new 
  species, 
  

   anterior 
  end 
  to 
  the 
  right. 
  X 
  7. 
  

  

  the 
  tooth 
  or 
  may 
  be 
  nearly 
  obsolete. 
  The 
  posterior 
  arm 
  of 
  the 
  

   protoconid 
  may 
  or 
  may 
  not 
  unite 
  with 
  the 
  metaconid. 
  Measurements 
  

   of 
  teeth 
  (in 
  millimeters): 
  

  

  M\ 
  Mt 
  Ml 
  

  

  Mi-x 
  • 
  

  

  USNM 
  No. 
  Length 
  Width 
  Length 
  Width 
  Length 
  Width 
  

  

  18772 
  (Type) 
  7.7 
  2.6 
  1.9 
  2.5 
  2.2 
  2.3 
  2.2 
  

  

  18771 
  8.0 
  2.8 
  1.9 
  2.4 
  2.3 
  2.7 
  2.2 
  

  

  18768 
  7.9 
  2.6 
  2.1 
  2.6 
  2.4 
  2.5 
  2.3 
  

  

  18770 
  7.4 
  2.4 
  1.9 
  2.5 
  2.2 
  2.3 
  2.1 
  

  

  18776 
  7.6 
  2.6 
  1.9 
  2.4 
  2.2 
  2.4 
  2.1 
  

  

  18769 
  7.5 
  2.7 
  2.0 
  2.5 
  2.2 
  2.4 
  2.1 
  

  

  18764 
  8.2 
  2.8 
  2.1 
  2.6 
  2.4 
  2.7 
  2.3 
  

  

  18776 
  7.5 
  2.7 
  1.9 
  2.4 
  2.3 
  2.3 
  2.1 
  

  

  18779 
  7.6 
  2.5 
  2.0 
  2.5 
  2.3 
  2.4 
  2.2 
  

  

  18773 
  7.5 
  2.5 
  1.9 
  2.4 
  2.1 
  2.4 
  2.1 
  

  

  18767 
  8.1 
  2.8 
  2.0 
  2.6 
  2.3 
  2.7 
  2.0 
  

  

  Eumys 
  spokanensis, 
  new 
  species 
  

  

  Holotyjpe.—V^'^M 
  18833 
  (fig. 
  47), 
  right 
  mandible 
  with 
  M1-3. 
  

  

  Horizon 
  and 
  locality. 
  — 
  Middle 
  Oligocene, 
  Orellan; 
  SEJ^SE}^ 
  sec. 
  10, 
  

   T. 
  10 
  N., 
  R. 
  1 
  W., 
  of 
  the 
  Montana 
  prime 
  meridian, 
  about 
  ]{ 
  mile 
  

   southeast 
  of 
  Canyon 
  Ferry, 
  Lewis 
  and 
  Clark 
  County, 
  Mont. 
  

  

  